Chemical vapor deposition is a process in which a raw material supplied into a reaction chamber in a vacuum state is decomposed using heat or plasma and is then chemically reacted to deposit a film on a substrate.
A conventional chemical vapor deposition apparatus is configured to include a reaction chamber that is isolated from the outside and maintains a vacuum; a raw material inlet for supplying a raw material into the reaction chamber; a heater for chemically reacting the supplied raw material; an outlet for discharging a process gas; and a susceptor positioned in a center of the reaction chamber and provided so that an object to be deposited or a substrate is placed thereon, wherein film deposition occurs on the object or the substrate.
In the above chemical vapor deposition apparatus, there is a problem in that the process gas flowing into the reaction chamber is undesirably deposited on an inner surface of the reaction chamber, a showerhead, and the like. The resultantly formed film is peeled from the portion on which the film is deposited due to various reasons such as repeated thermal expansion and contraction and acts as a contaminant source which contaminates an inside of the reaction chamber, thereby significantly reducing the overall production yield.
In order to solve this problem, a solution in which an internal chamber is provided in the reaction chamber not to allow the process gas to come into contact with the inner surface of the reaction chamber and, in some cases, only the internal chamber can be detached and replaced to prevent a process delay caused by a cleaning process from being generated has been proposed.
However, since the above internal chamber is disposed on a lower side of the reaction chamber and is fixedly mounted to an inside of the reaction chamber, a method in which an upper plate (a lid) of the reaction chamber is raised and moved together with an inner barrel has been utilized, in order to replace the substrate or the susceptor after the deposition process.
In this case, the inside of the reaction chamber is open, and the vacuum in the reaction chamber cannot be maintained. Therefore, there is a problem in that the overall productivity is deteriorated.